Various electronic devices are mounted at the car. For supplying electric power and transmitting signals to the various electronic devices, an electric connection box is arranged at the car (see patent documents 1-3).
The electric connection box having various structure is used. For example, the electric connection box 201 shown in FIG. 22 or the electric connection box 301 shown in FIG. 23 is for connecting a plurality of wiring harnesses 206, 207, 208 to each other according to a predetermined combination. Each of the electric connection boxes 201, 301 includes a case main body 203 receiving connectors 209a, 209b joined with an end of an electric wire 211 of the wiring harness 206, 207 or 208, an upper cover 204 covering an opening 203a at a top of the case main body 203 and a lower cover 205 covering an opening 203b at a bottom of the case main body 203.
The above electric connection box 201, 301 is assembled in following steps. First, the upper cover 204 and the lower cover 205 are removed from the case main body 203. Second, the connector 209a of the one wiring harness 206 is mounted into the case main body 203, and an electric wire 211 of the wiring harness 206 is led from a wire lead outlet 214 to an outside of the case main body 203. Next, the connector 209b of the other wiring harness 207 or 208 is fitted with the connector 209a of the one wiring harness 206, which connector 209a is mounted at the case main body 203, and the electric wires 211 of the other wiring harnesses 207, 208 are led out through wire lead outlets 215 to the outside of the case main body 203. Finally, the upper cover 204 and lower cover 205 are attached to the case main body. Thus, an operation of assembling the electric connection box 201 or 301 is completed.
As mentioned above, the connectors 209b of the other wiring harnesses 207, 208 are fitted to the connector 209a of the one wiring harness 206 and are fixed at the case main body 203. By inserting a hand from the opening 203a at the top of the case main body 203, operations of fitting the connector 209b with the connector 209a are acted.